Autonomous vehicles, such as vehicles which do not require a human driver, can be used to aid in the transport of passengers or items from one location to another. With a typical taxi or car service, a human driver can interact with a passenger to identify himself to that passenger. However, when an autonomous vehicle attempts to pick up a passenger or drop off a delivery, it can be difficult for the user being picked up or retrieving the item to know which autonomous vehicle is assigned to them. This can be exacerbated if there are numerous vehicles being sent to the same location to pick up multiple passengers or items. A passenger may not know how to confirm which vehicle belongs to him or her. As an example, this can also lead to passengers interacting with vehicles which were not assigned to them.